Hydraulic jack



INVETOR H P- BRUMDER HYDRAULIC JACK Filed Aug l5' :L91sa AITORNEY- APY22, 1941.

Patented Apr. 22, 1941 UNITEDv STATES PATENT OFFICE HYDRAULIC JACKHerbert P. Brumder, Chenequa, Wis., assignor to Blackhawk Mfg. Co.,Milwaukee, Wis., a corporation of Wisconsin Application August 15, 1938,Serial No. 224,881

3 Claims.

wheels or the like. 4In an effort to produce durable.

jacks at'moderate cost, the manufacturers of some of these devices haveheretofore resorted to' diecasting in the construction of the majorparts, and ln order to obtain a compact assemblage some of these jacksare formed with the liquid supply reservoir surrounding the plungerbarrel and with the pump cylinder and piston detachably associateddirectly with the base oi' the jack and disposed at an oblique anglerelative to the axis ofmovement of the jack plunger. The hydraulic jacksof this latter type have proven quite satisfactory in use, `but rathertedious, to construct by the die-casting method because some of thevalves 'and numerous ports were located within the relatively large andbulky base casting, and the rather delicate valve seats and liquidpassages were diillcult to form and to machine. The

manufacturers of these Jacks were therefore confronted with manydiilicultierin quantity production, and in the production of high gradeJack due to clogging of liquid passages or escape of actuating liquid.

A clear conception of an embodiment of my present invention, and of themanner of constructing and of utilizing a hydraulic jack built inaccordance with my improvement, may be had by referring to the drawingaccompanying and forming a part of thisspecification wherein like refer-'ence characters designate the samel or similar parts in the severalviews.

Fig. 1 is a part sectional side elevation of one of my improvedhydraulic jacks, the section being taken centrally through the pump andvalve assembly; and

Fig. 2 is a transverse horizontal section through the jack of Fig. 1,taken along the line 2-2.

Although I have shown and described my invention herein as beingspecifically applied to a units which could be sold at moderate cost andIn accordance with the present improvement, the.

jack barrel and the liquid supply reservoir surrounding the barrel, areformed integral with the base and are'connectible with each other forthe transfer of liquid from the reservoir to the barrel and vice versa,through a single relatively large and easily formed passage. The valvesand the relatively smaller suction', discharge and by.. pass ports of myimproved jacks are `all disposed within a rather simple pump casingwhich is detachably secured to the base in open communication with thereservoir and with the single large passage yin the base casting. Thus,aside from facilitating manufacture of the assemblage, the controlvalvesare made more readily accessible by mere removal of the pump from thebase, and the entire jack is less apt to become ineffectivehydraulically actuated automobile jack, it is not my intention tothereby unnecessarily restrict the scope and utility of the improvedfeatures.

Referring to the'drawing, the improved hydraulic jack assemblage` showntherein comprises in general a main support or base 5 having a plungerbarrel 6 and a liquid reservoir forming wall 1 formed integral with thebase and projecting upwardly therefrom; a plunger 8 movableapproximatelyvertically within the barrel 6 and having a cup-shapedflexibleseal 3 at its lower end coacting with the bore I0 of the barrel;a

vclosure cap II detachably secured to the wall 1 'and enclosing the topofthe liquid supply chamber or reservoir I 2, and coacting with theplunger 8 to guide the same; a pump casing or cylinder I3 detachablysecured to the base 5 and having a central bore Il which is communicablethrough ports I 5, I6 with the reservoir I2 and withI the barrel boreI0, respectively; a relatively large single passage I 'l formed in thebase 5 in axial alinement with the cylinder I3 and directly connectingthe lower extremity of the bore I0 with an enlarged lower portion I8 ofthe pump discharge port I6; a by-pass duct I9 formed in the cylindercasing I3 and connecting the port portion I8 with the reservoir I2, andhaving therein a manually manipulable relief valve -2li; a pump piston2l reciprocable within the casing bore I4' and an operating lever 22pivotally suspended from the base 5 and wall 1 by means of a fulcrum pin23, and coacting through a transverse pin 24 vsiilbh a. notch in theupper portion of the piston The base 5, barrel 6 and wall l, are reformed of suitable metal by die-casting? inflsl known manner, and' theborev I0 and annular which is adapted to be manipulated'fromntheexterior of Ithe jack through handles 411. The

. spindle 42 is embraced by a packing 45 which the reservoir chamber l2through one or more openings 25. The cup-seal 9 may be clamped to a disk2S coacting with the lower end of the plunger i8, by means of a nut 2l;and the upper extremity of the plunger 8 is provided with an adjustablescrew head 28 of usual construction. The detachable upper closure cap ll is adapted to coact with the head 28 as shown in Fig. l, when thelatter is in -lowermost position, and this cap i l may be provided withsuitable packing it coacting with the plunger 3. The outer wall l may beprovided with integral ears 3@ in which the pvot pin 23 is mounted andwhich also reeniorce the inclined socket 3l within which the cylindercasing it is confined, and this wall l may also be connected to the base5 by reenforcing ribs 32 likewise formed integral with these elements.

The cylinder casing i3 Within which all of the control valves areconfined. may also be formed as a die-casting,` and is conned within thesocket 3l with its medial portion completely surrounded by liquid in thesupply reservoir I2. The pump casing i3 is provided at its lower endwith a reduced portion 33 snugly fitting a counter-bore in the base 5,and with a plane lower end surface coacting with an adjacent surface ofthe base casting; and the upper end p0rtion 34 of the casing i3 is ofenlarged diameter and snugly ts the bore of the socket 3|. cylindercasing I3 is normally detachably clamped in position bv-means of a-ringnut'35, and the piston 2l which is slidable within the bore l@ of thecasing i3, is embraced by a packing 36 and a packing retainer nut 37which prevent escape of liquid along the piston. As previouslyindicated, the piston 2l is reciprocable by means of the pin 24 carriedby the lever socket 22, and a handle 38 may be secured to this socketand constitutesa part of the actuating lever. lower end of the piston 2Iis also provided with a cup shaped seal 39 which cooperates with thepacking 36 to prevent leakage'.

'The pump discharge port I 6 which connects the pump bore I4 with thelarge base passage I'I, has a ball discharge valve 4U confined thereinabove the by-pass'port I9, by means of a spring or snap ring in a wellknown manner; and the pump inlet or suction port I5 which'drectlyconnects the pump bore I4 with the reservoir I2, has a ball suctionvalve 4I confined therein by a similar snap ring. fWhile the dischargeport I6 is rectilinear throughout its entire length, Vthe suction portI5 is preferably formed of two rela-` tively inclined sections one ofwhich is` parallel to the bore I4. and the other of which is approxi.-mately parallel to the by-pass port I9, so as -to permit convenientformation of all of the ports I5, I6, I8, I9 by die-casting operations.AThe ball by-pass valve 20 which is also confined within the cylindercasing I3 and is removable therewith, is adapted to be pressedgagainstits seating to close the-port 19 when the pump is being operated, bymeans of a spindle 42 having screw thread coaction with a threadedelement 43, and

The

Thev

is retained in place by the element d3, and when the pump is inactiveand the spindle d2 is manipulated to release the by-pass valve 2l]liquid subjected to' pressure within the bore Ill and passage Il will bequickly relieved of such pressure by the escape of excess liquid throughthe ports i8, I 9 to the reservoir l2. In order to properly position theport i9 and the by-pass valve 20 relative to the spindle l2 when thecylinder casing I3 is placed within the socket 3l, the cylinder casingi3 may be provided with a recess adapted to coact with a key d6 formedintegral with the base 5, as shown in Figs. l and-2, and this key i6will positively prevent rotation of the pump cylinder.

During normal use of my improved jack assemblage, the reservoir chamberl2 andthe other confinedl spaces of the jack are supplied with liquid asshown in Fig. l, and when the plunger il is in lowermost position, theby-pass valve 2u .would ordinarily be closed. The lever handle 38 maythenbe oscillated to reciprocate the pump piston 2l, and as this pistonis elevated, liquid will be withdrawn from the supply chamber I2 throughthe port i5 and past the suction valve lil into the pump bore l@ beneaththe piston 2l. When the piston 2l is subsequently forced downwardly, theliquid in the pump displacement chamber will be forced through thedischarge port it past the delivery valve ill and through the passage llinto the bore i8 beneath the plunger cup seal d, thus causing theplunger 8 to rise. Repeated reciprocation of the pumppiston 2l willobviously cause the plunger 8 to rise 'higher and higher, until the seal9 passes the relief opening 25, whereupon the plunger movement willautomatically ceaseand excess liquid will escape from the bore l to thesupply charn- 'l From the'foregoing detailed description it will l beapparent that the present invention provides an extremely simple,compact and durable jack assemblage which can be readily constructed'and which is moreover conveniently manipulable. The mapor parts of theimproved jack may obviously be effectively produced by die-castingbecause of the fact that the base 5 has no complicated and undulyrestricted ports and passages therein, and further because of the factthat all of the relatively small ports as well as all of the valves areconfined directly within the pump casing I3. This pump cylin'dercasingis readily removable from the confining socketl 3| together with thevalves 2l), 40, 4I, and the relatively small ports in the pump. casingwill likewise permit convenient manufacture of this casing bydiecasting. The imp'rovedV assemblage embodies no ports or passageswhich are not freely accessible at all times for inspection andcleaning, and proper assembly of the pump and base isobviouslyfacilitated by the provision of the key 46 for insuring proper alinementof the spindle 42 with the by-pass valve 20. The improved jackassemblage may moreover be'malntained tight independently of the jackparts, and all of the n parts may be quickly assembled to complete thestructure. All of the elements of the improved jack may obviously bereadily formed and machined, and an abundant supply of liquid fromtherese'rvoir l2 to the pump and to the jack is constantlyavailable. i

,It should be understood that it is not desired to limit this inventionto the exact details of construction or to the precise mode ofoperation, herein shown and described, :for various medincations withinthe scope of the claims may occur to persons skilled in ,the art.

I claim: i

1. A jack comprising, an upwardly extending plunger barrel and anannular reservoir formed integral with and surrounding said barrel, saidbarrel Aand reservoir having an inclined upwardly open socket in opencommunication at its medial portion with said reservoir and the lowerend of which communicates directly with the lower extremity of saidbarrel through a large passage formed concentric with the socket, a pumpcylinder having opposite ends slip iitted within the lower and upperends of said socket and being provided with a central piston bore, oneside of the bottom of said piston bore being connected of whichcommunicates directly with the lower extremity ci said barrel through alarge recf tilinear passage formed concentric with the socket, a pumpcylinder having opposite ends tted within the lower and upper endsrespec- Ytively of said socket and being provided with a central pistonbore, one side-.of the bottom of said piston bore being connected withsaid concentric passage by a, rectilinear port having a discharge valvetherein and the other side of said bottom being connected to saidreservoir by an angular port having a suction valve therein while theportion of said rectilinear port between said discharge valve and saidpassage communicates through an outwardly directed by-pass port hav'-ing a by-pass valve therein directly with said reservoir, all of saidports being formed wholly within said cylinder and lying in a commonplane means for positively preventing rotation of said cylinder aboutits own axis when disposed within said socket, and a spindle movablefrom theexterior of said reservoir in axial alinement with said by-passvalve poit for manipulating said by-pass valve.

3. A jack comprising, an upwardly extending plunger barrel surrounded byan annular reservoir formed integral with said barrel, said barrel andreservoir having an inclined upwardly open socket in open communicationat its medial porwith said concentric passage by a rectilinear porthaving a discharge valve therein and the other side of said bottom beingconnected to said reservoir by an angular port having a suction valvetherein while the portion of said rectilinear port between said.discharge valve and said passage communicates through an outwardlydirected bypass port having a by'pass valve therein directly with saidreservoir, all of said ports being formed wholly within said cylinderand lying in a cornmon plane, and means operable from the ex-` tion withsaid reservoir'and the lower end of which communicates directly with thelower extremity of said barrel through a large rectilinear passageformed concentric with the socket, a pump cylinder having lower andupper ends slip fitted within the lower and upperends respec-l tively ofsaid socket and being provided with a central piston bore, one side ofthe bottom of said piston bore being connected vwith said ,concentricpassage by a rectilinear port having a discharge valve therein and theother side of said bottom being connected to said reservoir by anangularport having a suction valve therein while the portion of saidrectilinear port between said discharge ,valve and said passagecommunicates outwardly directly with said reservoir through a bypassport having a by-pass valve therein, all of P. BRUMDER.

